seattle, morning showers, 44. >>> it's a longstanding christmas tradition in new york city where thousands gather together to sing a famous piece of coral music. it's being celebrated to show the holiday spirit. tony guy da reports. ♪ >> reporter: all year long people fill new york's avery fisher's hall to listen to music. one night a year they come to sing. it's a christmas tradition. ♪ 2,000 people, strangers, uniting as a chorus to perform one of the most familiar pieces of music in the world, handel's "messiah." >> it has everything in it you can look forward to. melodic tunes, rich choruses, emotions, joy, interspekz and more. >> reporter: no wonder there are song-a-long messiah's across the world, much of them in the english-speaking world. ♪ halleluiah ♪ >> reporter: at the memorial church a few miles from avery hall the voices are smaller but spirits are just as strong. this was her first "messiah. . >> you just feel joy use and overwhelming. >> reporter: josh has been coming for decades as a cure for wintertime blues. >> i'm sheer deep down we're not sure that life's going